A Percolation Area – Explained
What does the term percolation mean?
Percolation is simply the process of liquid slowly passing through a filter, for example it is how coffee is made. For a septic tank, the percolation area is an area of soil where treated wastewater is discharged into the ground.
What are the common problems with percolation areas?
There is a number of problems that may occur with your Percolation Area or Septic Tank. One of the most obvious signs that there is something wrong is that there will be a foul smell. Cracks on the lid or on the walls of your tank is also a cause for concern. It is also important that you de-sludge your tanks regularly otherwise solid untreated materials will overflow into the outlet of your tank, which will then accumulate in the percolation pipework. When septic tanks are not serviced and de-sludged in the recommended time the pumps and blowers will burn out due to the added pressure.
What is a percolation test?
In order to ensure your building site is suitable for a septic tank, a percolation test or “perc test” is required. The perc test will determine the soils absorption rate for a “leach field” or a septic tank drain field. The results of the perc test are required to design your septic tank accordingly.
How to carry out a percolation test?
A percolation test can be carried out by digging a hole at 300mm square to a depth of around 250mm at the site where a septic tank is proposed to be installed. The soil is then saturated fully with water and leave overnight. Refill the hole with water and record the time taken for the water to seep away. Once the water has completely seeped away from the hole, divide the time taken for the water to disappear by the depth of the water in the hole.
Try this same test in 3-4 other trial holes at your site and compare results in each to determine the best suitable place for your septic tank at your site.
How far does my septic tank need to be from my house?
To meet the septic tank regulations, the distance required is 7 meters, if you are unsure about the measurements you can contact us and we will be happy to advise you.